At LvL200, the attack will be poor because of the CRT penalty for special sword, or VIT penalty if you choose special bow. I reckon you'd barely have 1k ATK even with the help of ATK xtals (since you don't have weapon mastery (your best bonus is Battle Mastery, and your only ATK buff is a warcry))
I would find it easier to build and level a guardian pally than an auto attack pally, which is why I don't think an auto attack pally is a viable build.
That's true with either of those weapons. You have to be careful about it. Spec bow has some advantages though.
Nail is 2atk agi, 2atk str
Spec sword 1 atk str, 2 atk vit, 1.5atk dex, -1atk crt
Spec bow -1 atk int, -1 atk vit, 2 atk agi, 1 atk crt
With a vit/agi/crt build, nail's getting atk from agi.
Spec sword from vit, a minus from crt, and 1atk overall.
Spec bow from agi/crt, a minus from vit, and 2 atk overall.
In theory it's the same dmg as nail, whereas a nail can add str for 2 atk more, or a spec bow could add dex (with thimble) for 1 atk more.
Either way the maximum on spec bow is 4 points (with thimble), 4.5 points on spec sword, and 4 points on a nail. So, in theory the dmg would be similar to other characters despite being paladin...
However, it doesn't work that way because all stats have to be equal and maximum. It's the maximum potential for the builds. While building the character, stats won't be so even; so, it's a constant concern.
The 256 vit, 200 crt, 140 agi example I gave. With nail that'd be similar atk/dmg to a character stats of a level 110-ish.... Pretty awful.
With spec sword... it's roughly 1 point of atk overall... Half as much base atk as a cap agi / 200 crt character... Most likely well below 1k (I'm thinking 700).
With spec bow... there's 200 atk plus 280 atk from the agi, which is mostly canceled by the vit. So, you're looking at 224-ish atk + base atk of the weapon. Our spec bow has low base atk, so it's even worse dmg than the nail.
The thing is though, at near lvl 250 when 3 stats cap. Vit/crt/agi is overall worth 2 points to atk. Half as much as a dps at that level would have, or the same as a cap agi / cap crt player now. Medicore, but that character's a paladin, not a dps. And, after 3 stats cap the rest can move to dex for a more traditional paladin. (Also, using a thimble there is a little more gain to atk.)
Vit/crt/agi is with nails is just another option. Same dmg, just choose str as fourth stat. Probably a little stronger (closer to the full 4 points).
Even spec sword could vit/dex/crt berserk build and have overall about the same dmg (2.5 points). Or, it could support the missing agi with equipment and still have similar dmg as the previous auto-hit builds (the bonus from extra .5 points is lost to support agi).
Vit/int/crt w/ magic sword is same dmg (exactly same as above). Could support agi the same as spec sword build and has similar dmg. There is the now the option of magic sword skills and a more sizeable pool of mp (a longer berserk as well).
Vit/str/crt utilizing element swords and supporting the agi with gear may be a little stronger though. 3 points to atk (slightly more atk than nail) and it maximizes guardian dmg. Either way, it's the more/most expensive option.
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Really, the issue is becoming getting there (to the level where a build becomes as intended). Each weapon has it's benefits. Dmg directly comes from crt as an auto-hit dps; so, spec bow has an advantage as one also gets some atk from adding crt. (Maybe it's useful for lower levels.) When vit comes into play, nails are are more useful (because of the negative to spec bow). The builds without agi will all struggle in the lower levels, I think (but am not 100% certain). It all comes down to play style, but the final result (near lvl 250) is fairly balanced regardless of the choice in stats or weapon.
Anyway, dps paladins are going to have low dmg, but I'm thinking the idea is to give paladin another method of playing the game. Such as allowing them an opportunity, albeit at a disadvantage, to do some things without having to party for a change.
Personally, however, I think this type of build possesses one of the strongest solo'ing capacities in game. Ya, it's an incredibly inefficient build, but it'd probably pull some interesting things off (with way too much effort, of course).
And, also, there's the issue of no dmg/atk buffs for pally class; so, even though the numbers add up, the dmg will be less. Anyways, out of all the builds I listed up there. I'm in preference for a magic sword build that forsakes dmg (crt) for about 200 agi.
Edit:
Thinking about it... the magic sword build auto-hit pally may be gamebreakingly op...